1. Field of the Invention
The present invention relates to a device utilized to either tighten or loosen the threaded connection of a brake caliper and a brake line, and more particularly to a device having a rotatable surface for supporting and rotating the brake caliper relative to the brake line.
2. Description of the Prior Art
Typically, a disc brake system is provided with a rotor and an associated caliper having at least two friction pads and pistons. The pistons engage the friction pads to force the pads against the rotor. The resulting contact between the friction pads and the rotor restrains rotation of the rotor, thus decreasing the speed of the vehicle.
After substantial repetitive use of the disc brake system, it is often necessary to do such maintenance work as change the friction pads, replace one or more of the pistons, or replace the entire caliper. To aid the mechanic in this work, many tools have been developed especially for brake system maintenance. A plurality of these tools have been for retracting the pistons into the caliper to facilitate replacement of the friction pads. With the pistons retracted inside the caliper, there is sufficient clearance for the worker to access and remove the friction pads.
Tools utilized for retracting a piston into a caliper are disclosed in U.S. Pat No. 3,580,544 issued to Arthur Albert Payne on May 25, 1971, U.S. Pat. No. 4,671,144 issued to Mark F. Zeller on Jun. 9, 1987, and U.S. Pat. No. 4,845,823 issued to Ernest E. Shipman on Jul. 11, 1989. The Payne patent teaches a tool for insertion between the piston and the disc such that rotation of the tool forces the tool face into the piston to force it to retract into the caliper, thus allowing the friction pads to be replaced. The Zeller patent relates to a generally U-shaped clamp for placement over part of the caliper housing. With this clamp in the appropriate location, the front walls of the clamp cover the pistons to prevent them from protruding outward from the caliper. The Shipman patent discloses a tool having a plurality of plier-like handles at one end and two caliper engaging surfaces at the other end. Displacement of the handles permits the caliper engaging surfaces to apply spreading forces to the brake pads which increase the distance between the pads while simultaneously forcing the associated caliper pistons to retract into the caliper.
Other tools utilized to increase the efficiency of maintenance work on disc brake systems are disclosed in U.S. Pat. No. 5,003,681 issued to Paul E. Schley on Apr. 2, 1991, U.S. Pat. No. 5,077,886 issued to Kenji Hashimoto et al. on Jan. 7, 1992, and German Pat. Specification No. 241,878 issued to Wilfried Muller et al. on Jan. 7, 1987. The Schley patent discloses a tool for rotating a brake piston. This tool includes a rim extending from and surrounding the working face of the tool. When the tool is placed over the face of the piston, the rim grips the piston which may then be rotated by rotating the tool. The Hashimoto et al. patent discloses an automated brake caliper mounting apparatus for inserting a brake disk into the gap between the friction pads of a caliper. This apparatus includes a working arm capable of carrying the caliper from a caliper supply station to a jig pallet where the brake disc is inserted into the caliper by the working arm. The Muller et al. patent specification shows a workpiece clamping assembly having several clamps for arrangement around the outer perimeter of the workpiece.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.